Abstract:
Manganes oxide has structures such as layered, tunnel, and amorphous. Birnessite is a mangane oxide with layered structure. Birnessite has never been found in a pure form in nature. The pure birnessite can be obtained by synthesis in laboratory. In this research, birnessite is synthesized from solids of KMnO4 and fumaric acid using ceramic method. The typical synthesized of birnessite can be carried out by varying mol ratio, temperature, and calcination time of reactants. The products are then characterized by XRD for purity and crystalinity, SEM for morphology and particle size, AAS for chemical composition, and IR for functional group and acidity. The XRD results showed that the number of mol ratio of oxidating agent KMnO4 over reducing agent fumaric acid strongly influenced by the formed manganese oxide phase. An increase in time and temperature of calcination also affects the crystalinity and purity. The optimum conditions of reaction production of improved crystalinity and purity are 3:1 for mol ratio of KMnO4 to fumaric acid, 700 0C for calcination temperature and 7 hours for reaction time. The formation of birnessite is also supported by the presence of 520 cm-1 peak characteristics for birnessite. The synthesized birnessite has surface area
between 0.1951 m2/gr and 0.9596 m2/gr with plate-like appreances in which K and Mn
contents are 22% and 60%, respectively
